PGA champ Jimmy Walker coping with mononucleosis

Jimmy Walker, who poses with the trophy after winning the PGA Championship golf tournament last year, is set for another run at Augusta. (AP Photo/Seth Wenig)

AUGUSTA, Ga. (AP) — PGA champion Jimmy Walker says he has been coping with mononucleosis that has contributed to his lethargic play.

Walker captured his first major last year with a wire-to-wire victory in the PGA Championship, contended in the second FedEx Cup playoff event and went 1-2 in his matches at Hazeltine when the United States won the Ryder Cup.

He has spent most of this year trying to figure out why he has felt so sluggish and finally was diagnosed with mono.

"I haven't passed it on to the kids or to (wife) Erin, so that's good," Walker said. "I've just felt so bad all year. I've had glucose testing, Lyme disease testing and we finally got it figured out."

Walker said he began experiencing flu-like symptoms at Thanksgiving. The only tournaments he played after the Ryder Cup were a last-place finish at the HSBC Champions at Shanghai and a missed cut in Las Vegas. He also played in the Hero World Challenge in early December and tied for 15th in an 18-man field in the Bahamas.

"I've just been totally lethargic," Walker said. "I've had no energy. I get to the golf course and I just want to sit down. I was not about to say anything. I just kept plugging along."

He said outside his family, only caddie Andy Sanders, swing coach Butch Harmon and his psychologist were aware.

Walker said the only remedy is rest, "and I don't have time for that."

He can only wonder how much his energy level has affected his play. Walker has broken par only one time in the final round this year, a 69 at Riviera. A week ago, he shot a 79 on Saturday and missed the 54-hole cut.

He spoke earlier in the day about taking in all that the Masters has to offer.

"I think it's a week I always try to slow down and enjoy it, because it's so cool to be here," Walker said. "It such an experience and it's fun to watch the people. Try to slow down and enjoy."

Walker, who will be paired with world No. 1 Dustin Johnson and 2-time Masters champion Bubba Watson, will tee off around 1:03 p.m. Thursday.

This will be Walker's fourth Masters, tied for 8th in 2014 for his best showing at Augusta.